The present invention relates generally to agricultural round balers and more particularly to a method for staggering routing of adjacent side-by-side belts to reduce debris collection behind the belts.
Round balers have become quite prevalent for their capability of producing a conveniently sized cylindrical bale, very often automatically wrapped with a sheeting material such as net or film. Prior art round balers generally have a bale-forming chamber defined by a pair of spaced-apart side walls and a series of parallel belts trained around a series of rolls spanning between the side walls. A pick-up mechanism picks up crop material, such as hay, from the ground as the baler travels across the field, and is fed into a fixed or expandable chamber where it is rolled up to form a compact cylindrical hay package. While still inside the bale-forming chamber in its compacted form, the outer surface of the package is wrapped with twine or other wrapping material, such as film or net, prior to ejection of the wrapped bale from the chamber onto the ground for subsequent handling.
Round balers typically include a series of parallel rolls mounted between spaced sides, with a series of side-by-side belts trained about the rolls. The belts extend across a crop inlet defined between a pair of spaced rolls, and a pick-up mechanism feeds crop rearwardly to the crop inlet as the baler is moved along a windrow of crop material. As crop material is forced into the inlet, the belts deform inwardly into a rotating bale-forming chamber which compresses the crop material to form a round bale. The belts are trained about a tensioned take-up mechanism, which accommodates bale growth while maintaining tension on the belts. U.S. Pat. Nos. 4,870,812 and 5,367,865 issued to Jennings et al., disclose such prior art round balers having an expandable bale chamber defined by a pair of fixed sidewalls, and a plurality of side-by-side belts cooperating with a series of transverse rolls, mounted between a pair of pivotally mounted arms commonly known as a sledge. The chamber includes an inlet opening in the front through which crop material is fed. Also included is a pair of take up arms pivotally mounted on the main frame, between which arms a pair of guide rolls are journalled. A biasing force on the take up arms urges the outer surfaces of the guide rolls against the belts to maintain tension and thereby prevents slack from occurring in the belts during expansion and contraction of the chamber.
In a round baler of this type, it is important that the belts remain in contact with the rolls in order to ensure proper belt tracking and advancement. In the past, it has been known for crop material to adhere to the belts as the belts exit the bale-forming chamber. This material, which is commonly known as “trash” because it is not incorporated into the bale, can build up on the rolls and adjacent the sides of the baler, causing belt driving and tracking problems which hinder the performance of the baler and which, in severe cases, may actually stop operation of the baler. Known methods for reducing trash build-up behind the belts is to stagger adjacent belts in order to create openings through which trash can pass and be directed to a desired location for recovery in the baler. The stagger in the belts is caused by providing an offset roll around which some of the belts travel and routing belts around different contact points on the rolls (e.g., some travel across the front, while others travel across the back of the roll). These known methods require the use of belts having differing lengths to accommodate the different belt paths, use of additional offset roll assemblies, and/or adjacent co-axial roller sections that rotate opposite directions, all of which increase manufacturing complexity of the baler.
It would be desirable to provide a mechanism for guiding the roll belts in a round baler which staggers adjacent belts thereby creating openings through which trash can be directed while retaining a relatively simple roll drive mechanism and allowing use of a plurality of equal-length drive belts. Additional advantages would be realized in a mechanism for guiding the roll belts in a round baler that minimizes bends in the belt path.